November 15, 2012

Researchers Discover Key Gene That Makes Humans Distinct From Apes

An international team of researchers, led by the University of Edinburgh, has discovered a new gene that helps to solve one of life's greatest mysteries — what makes us human?

The gene — miR-941 — helps to explain how humans evolved from apes. It appears to have played a crucial role in the development of the human brain and may shed light on our use of tools and language.

This is the first time, according to the team, that a new gene carried only by humans and not by apes has been shown to have a specific function within the human body. They compared the human genome to 11 other species of mammals — including chimpanzees, gorillas, mice and rats — to find the differences between them.

The miR-941 gene is unique to humans, the study found. The results, published in Nature Communications, show that it emerged after humans evolved from apes, between six and one million years ago.

The team found that the gene is highly active in the two areas of the brain that control a human's ability to make decisions and our language abilities, suggesting that it could have a role in the advanced brain functions that make us human.

Most differences between species occur as a result of changes to existing genes, or the duplication and deletion of genes. Scientists say, however, that this gene emerged, in a startlingly brief interval of evolutionary time, fully functional out of non-coding genetic material. This material has been termed "junk DNA." Previous to this study, it has been remarkably difficult to see this process in action.

"As a species, humans are wonderfully inventive — we are socially and technologically evolving all the time. But this research shows that we are innovating at a genetic level too. This new molecule sprang from nowhere at a time when our species was undergoing dramatic changes: living longer, walking upright, learning how to use tools and how to communicate. We're now hopeful that we will find more new genes that help show what makes us human," explained Taylor in a statement.